The field of this invention relates to shock isolating power transmitting couplings in which the engine power is supplied to the transmission input shaft through the use of the elastomeric material which is to minimize the transmitting of shock and vibration to the transmission.
At the present time, automotive engines are being mounted in boats without a torque converter attached between the engine and automatic transmission. The engine is directly connected to the automatic transmission and the automatic transmission then in turn, is directly connected to the propeller.
In the operation of any internal combustion engine, the power is not supplied at a continuous level. Each time ignition within the engine occurs, there is a power surge which then diminishes, and the next power surge and so forth. This uneven power level is made somewhat constant through the use of a flywheel. However, the effectiveness of a flywheel, particularly light weight flywheels, has not been sufficient to prevent shock and vibration being transmitted at undersirable levels through the automatic transmission. In normal operation of the boat, the automatic transmission will fail within a short period of time, since all automatic transmissions are designed to operate with a torque converter that absorbs shock. However, in a boat, the use of a torque converter causes energy losses. Therefore, it is undesireable to use such a torque converter.
There is a definite need for a device included within the drive train of a boat to substantially eliminate shock and vibration and prevent significant levels of such from being transmitted to the automatic transmission.
Although the structure of this coupling is designed or has been discussed primarily for use in boats, it is considered to be within the scope of this invention to employ the device in any engine environment.